Today it is easy to pretend that such a control is life-saving. But it is rather the sole reliance on this mechanism, according to the motto, I will probably be warned. This is a wrong attitude to want to feel comfortable embedded in electronics. By the way, even in the past you have driven without all these mechanisms and you have not always been on the brink of the abyss.

A little bit of feeling for the vehicle can't hurt even today. This also includes stopping in case of an indisposition with the conditions and moving your butt around the car, of course in a safe place if at all possible. Visual inspection is still a trump card, even in times when there is a lot of electronics in the car. So it is completely incomprehensible that people have lost a wheel, for example, because it is very noticeable before.

Nevertheless, a constant monitoring of the tyre pressure is of course a good thing. One would like to have it even more comprehensive, e.g. on a high-built caravan that is perhaps only fetched from a parking space once or twice a year. Of course the tyre pressure control cannot replace a first thorough check of the pressure and the tyres in general.

There is a clear objective for such a system. Of course, this does not include the sudden loss of air in the tyre. And again, the above-mentioned applies here: every driver should notice something like this and react to it as quickly as possible. No, tyre pressure control tends to reveal the gradual loss of pressure, which is particularly important because it often goes completely unnoticed, not only by changing drivers.

At this point, it should be remembered that a tyre on a drop centre rim is a fragile relationship that can be dissolved at any time if certain unfavourable circumstances coincide. One of these circumstances is simply the air pressure. If the air pressure is no longer high enough, when cornering, the same happens as a tyre changer does, namely the tyre bead is pressed inwards.

The consequences are fatal, because there is no stopping. The remaining pressure also escapes. A particular tragedy is that when cornering, the very tyre(s) on which you are most dependent goes belly up with too little pressure. It doesn't matter whether the tyres still remain on the rim in some way, even as shreds. They have lost their effectiveness, which in the best case transports the car to a neighbouring field.

Let us explore together how to avoid such an extremely unpleasant situation. Fortunately, nowadays you can't escape such a control system unless you buy an older car. This has been a legal requirement in Europe since 2014, and there are two ways of doing this, one quite expensive and complicated and one, perhaps not so precisely measured, but quite useful and much cheaper.

Let's start with number 2, where the wheels have remained as they have always been, which of course makes it much easier to exchange them in autumn and spring. The system could already be introduced when ABS was available more or less everywhere. It's actually a bonus, so it doesn't require any additional sensors. You simply use the wheel sensors, usually four. These are metal rings that rotate at wheel speed and pass the sensor at a small distance.

The sensor consists of a magnet wrapped with a bare, lacquered wire, which sends a current pulse of varying strength to the evaluating control unit, depending on whether a large or small amount of metal mass rushes past it. The whole system is so fast that it can reliably determine the respective wheel speed even beyond the maximum speed, actually all in all a simple counting process over time.

So, now all you have to do is digitally and electronically compare the speed of the wheels of one axle with each other and install a threshold at which the decreasing numbers of one of the two wheels compared to the other are reported to the cockpit. With this approach, the system would not even need to be calibrated. But, once again, it does not remain that simple. Because the two front wheels, insidious as they are, could lose their air to the same extent and the system would not notice it.

The adjustment with the rear wheels helps, you will have already thought of it. True, although now the difficulties begin. Because there are now several sporty cars with different wheel diameters at the front and rear. Also, the system would need some kind of delay in measuring, which does not respond even if someone, for whatever reason, crosses a roundabout twice.

Digital electronics is like administration, it virtually multiplies itself. Because of course one has thought about the perhaps very rare case that all four wheels could have the same error and lose the same amount of air per time unit. Our system described so far could not notice this. But it does have one advantage in advance: you neither have to worry about running out batteries in wheels nor does a workshop have to carry out any necessary adjustment.